Fundus camera

Abstract

A fundus camera capable of favorably obtaining a photographed fundus image and an observation fundus image, has an optical system having an objective lens and a diaphragm at a conjugate position with a pupil relative to the lens, for performing visible photographing and infrared observation via the lens and an aperture of the diaphragm, an optical system for illumination with visible and infrared light via the lens, a first plate, with a first black dot to cover an aperture image and at a conjugate position on an optical path with a position where a virtual image is formed relative to a lens surface reflecting the visible light, and a second plate, with a second black dot to cover an aperture image and in the vicinity of a conjugate position on the path with a position where a virtual image is formed relative to the surface reflecting the infrared light.

1. A fundus camera for photographing a fundus of an eye of an examinee, the fundus camera comprising:
 a photographing/observation optical system having an objective lens and a diaphragm arranged at a conjugate position with a pupil of the eye in relation to the objective lens, for performing visible photographing and infrared observation of the fundus via the objective lens and an aperture of the diaphragm; 
 an illumination optical system for illuminating the fundus with visible light for photographing and infrared light for observation via the objective lens; 
 a first black-dot plate provided with a first black dot that is in a size to cover an image of the aperture of the diaphragm and arranged at a position on an optical path of the illumination optical system, the position conjugate with a position at which a virtual image of the aperture of the diaphragm is formed in relation to a reflection surface in a case where the visible light for photographing is reflected by the objective lens; and 
 a second black-dot plate provided with a second black dot that is in a size to cover an image of the aperture of the diaphragm and arranged in the vicinity of a position on the optical path of the illumination optical system, the position conjugate with a position at which a virtual image of the aperture of the diaphragm is formed in relation to the reflection surface in a case where the infrared light for observation is reflected by the objective lens, wherein 
 the first black dot is arranged to be fixed on the optical path and shields at least the visible light for photographing, 
 the second black dot is arranged to be removable on the optical path and shields the visible light for photographing and the infrared light for observation, and 
 the second black dot is removed from the optical path at the time of the visible photographing and is inserted into the optical path at the time of the infrared observation. 
 
   
   
     2. A fundus camera for photographing a fundus of an eye of an examinee, the fundus camera comprising:
 a photographing/observation optical system having an objective lens and a diaphragm arranged at a conjugate position with a pupil of the eye in relation to the objective lens, for performing visible photographing and infrared observation of the fundus via the objective lens and an aperture of the diaphragm; 
 an illumination optical system for illuminating the fundus with visible light for photographing and infrared light for observation via the objective lens; 
 a first black-dot plate made of a glass plate and provided with a first black dot at its center that is in a size to cover an image of the aperture of the diaphragm which is arranged at a position on an optical path of the illumination optical system, the position conjugate with a position at which a virtual image of the aperture of the diaphragm is formed in relation to a reflection surface in a case where the visible light for photographing is reflected by the objective lens; and 
 a second black-dot plate made of a glass plate and provided with a second black dot at its center that is in a size to cover an image of the aperture of the diaphragms which is arranged in the vicinity of a position on the optical path of the illumination optical system, the position conjugate with a position at which a virtual image of the aperture of the diaphragm is formed in relation to the reflection surface in a case where the infrared light for observation is reflected by the objective lens, wherein 
 the first black-dot plate is arranged to be fixed on the optical path and the first black-dot shields at least the visible light for photographing and 
 the second black-dot plate is arranged to be fixed on the optical path, and the second black-dot is formed by a coating having a property of transmitting the visible light for photographing and shielding the infrared light for observation.